ef1f7df917
Split the expression ops into two parts and support overloading of the runtime expression ops based on the requested function through a ->select_ops() callback. This can be used to provide optimized implementations, for instance for loading small aligned amounts of data from the packet or inlining frequently used operations into the main evaluation loop. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
147 lines
3.9 KiB
C
147 lines
3.9 KiB
C
/*
|
|
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* Development of this code funded by Astaro AG (http://www.astaro.com/)
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/netlink.h>
|
|
#include <linux/netfilter.h>
|
|
#include <linux/netfilter/nf_tables.h>
|
|
#include <net/netfilter/nf_tables_core.h>
|
|
#include <net/netfilter/nf_tables.h>
|
|
|
|
struct nft_bitwise {
|
|
enum nft_registers sreg:8;
|
|
enum nft_registers dreg:8;
|
|
u8 len;
|
|
struct nft_data mask;
|
|
struct nft_data xor;
|
|
};
|
|
|
|
static void nft_bitwise_eval(const struct nft_expr *expr,
|
|
struct nft_data data[NFT_REG_MAX + 1],
|
|
const struct nft_pktinfo *pkt)
|
|
{
|
|
const struct nft_bitwise *priv = nft_expr_priv(expr);
|
|
const struct nft_data *src = &data[priv->sreg];
|
|
struct nft_data *dst = &data[priv->dreg];
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++) {
|
|
dst->data[i] = (src->data[i] & priv->mask.data[i]) ^
|
|
priv->xor.data[i];
|
|
}
|
|
}
|
|
|
|
static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
|
|
[NFTA_BITWISE_SREG] = { .type = NLA_U32 },
|
|
[NFTA_BITWISE_DREG] = { .type = NLA_U32 },
|
|
[NFTA_BITWISE_LEN] = { .type = NLA_U32 },
|
|
[NFTA_BITWISE_MASK] = { .type = NLA_NESTED },
|
|
[NFTA_BITWISE_XOR] = { .type = NLA_NESTED },
|
|
};
|
|
|
|
static int nft_bitwise_init(const struct nft_ctx *ctx,
|
|
const struct nft_expr *expr,
|
|
const struct nlattr * const tb[])
|
|
{
|
|
struct nft_bitwise *priv = nft_expr_priv(expr);
|
|
struct nft_data_desc d1, d2;
|
|
int err;
|
|
|
|
if (tb[NFTA_BITWISE_SREG] == NULL ||
|
|
tb[NFTA_BITWISE_DREG] == NULL ||
|
|
tb[NFTA_BITWISE_LEN] == NULL ||
|
|
tb[NFTA_BITWISE_MASK] == NULL ||
|
|
tb[NFTA_BITWISE_XOR] == NULL)
|
|
return -EINVAL;
|
|
|
|
priv->sreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_SREG]));
|
|
err = nft_validate_input_register(priv->sreg);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
priv->dreg = ntohl(nla_get_be32(tb[NFTA_BITWISE_DREG]));
|
|
err = nft_validate_output_register(priv->dreg);
|
|
if (err < 0)
|
|
return err;
|
|
err = nft_validate_data_load(ctx, priv->dreg, NULL, NFT_DATA_VALUE);
|
|
if (err < 0)
|
|
return err;
|
|
|
|
priv->len = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN]));
|
|
|
|
err = nft_data_init(NULL, &priv->mask, &d1, tb[NFTA_BITWISE_MASK]);
|
|
if (err < 0)
|
|
return err;
|
|
if (d1.len != priv->len)
|
|
return -EINVAL;
|
|
|
|
err = nft_data_init(NULL, &priv->xor, &d2, tb[NFTA_BITWISE_XOR]);
|
|
if (err < 0)
|
|
return err;
|
|
if (d2.len != priv->len)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr)
|
|
{
|
|
const struct nft_bitwise *priv = nft_expr_priv(expr);
|
|
|
|
if (nla_put_be32(skb, NFTA_BITWISE_SREG, htonl(priv->sreg)))
|
|
goto nla_put_failure;
|
|
if (nla_put_be32(skb, NFTA_BITWISE_DREG, htonl(priv->dreg)))
|
|
goto nla_put_failure;
|
|
if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
|
|
goto nla_put_failure;
|
|
|
|
if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
|
|
NFT_DATA_VALUE, priv->len) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
|
|
NFT_DATA_VALUE, priv->len) < 0)
|
|
goto nla_put_failure;
|
|
|
|
return 0;
|
|
|
|
nla_put_failure:
|
|
return -1;
|
|
}
|
|
|
|
static struct nft_expr_type nft_bitwise_type;
|
|
static const struct nft_expr_ops nft_bitwise_ops = {
|
|
.type = &nft_bitwise_type,
|
|
.size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
|
|
.eval = nft_bitwise_eval,
|
|
.init = nft_bitwise_init,
|
|
.dump = nft_bitwise_dump,
|
|
};
|
|
|
|
static struct nft_expr_type nft_bitwise_type __read_mostly = {
|
|
.name = "bitwise",
|
|
.ops = &nft_bitwise_ops,
|
|
.policy = nft_bitwise_policy,
|
|
.maxattr = NFTA_BITWISE_MAX,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
int __init nft_bitwise_module_init(void)
|
|
{
|
|
return nft_register_expr(&nft_bitwise_type);
|
|
}
|
|
|
|
void nft_bitwise_module_exit(void)
|
|
{
|
|
nft_unregister_expr(&nft_bitwise_type);
|
|
}
|